Hardwood Floors October/November 2025

By Tim Colgan

To evaluate sound performance, there are three types of sound typically considered: Step sound: The sound your neighbor hears when you are walking on the floor. Airborne sound: The sound that carries from voices, TV, or music. Drum sound: The sound you hear yourself when walking on your floor. Sound performance is measured by two ratings: Sound Transmission Class (STC): Evaluates airborne sound insulation through walls, floors, and ceilings. Impact Insulation Class (IIC): Measures how well a floor-ceiling assembly absorbs impact noise. In multifamily construction, the Uniform Building Code requires a minimum IIC of 50. Engineered floors, installed in conjunction with a quality acoustical underlayment will exceed the minimum IIC. Ratings of 60 or higher often are required for luxury buildings, where privacy is a key priority. To meet these benchmarks, flooring must work in tandem with underlayments and subfloor assemblies. Dense, resilient materials, such as hardened wood, can help reduce impact, especially when installed with compatible acoustic underlays. DURABILITY AND SUSTAINABILITY Multifamily floors face constant wear: foot traffic, pets, furniture movement, and spills. Durability affects how well a floor maintains its appearance over time, how often it requires repairs or replacement, and its overall lifecycle cost. Durability can be measured using the Brinell hardness test, which evaluates a material’s resistance to surface indentation. Hardened wood floors have been shown to be up to three times stronger than traditional wood flooring, offering greater resistance to dents, scratches, and moisture. This enhanced strength supports longer lifespans and reduced maintenance.

PHOTOS COURTESY OF BJELIN

Hardened wood builds upon engineered wood with added strength and moisture resistance. While still 100 percent real wood, it features a denser surface layer and optimized core materials that increase durability and make it well-suited to high-traffic, high-occupancy buildings. Advanced locking systems allow for faster installations – an advantage in large scale developments. With the types of wood floors in mind, it also is important to assess how they perform in common multifamily conditions. SOUND ATTENUATION: Noise is one of the most common complaints in multifamily buildings. Footsteps, dropped objects, music, and voices can carry easily between units. Flooring can either reduce or amplify these sounds, making sound attenuation a crucial factor in material selection.

the magazine of the national wood flooring association

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